A cylindrical metal disc, such as a coin, can be spun on a smooth surface. The spinning motion becomes a combination of spinning and rolling. Many physicists have studied the motion of such discs which they have named Euler Discs. All articles on such discs which were found by the present inventor referred to cylindrical discs in which the thickness at the perimeter is substantially equal to the maximum thickness.
U.S. Pat. No. 5,863,235 describes a steel cylindrical Euler disc. It has a thickness at the perimeter substantially equal to its maximum thickness. The claims of this patent are entirely restricted to the decoration on the upper surface of the disc.